How to Disable Driver Signature Verification In Windows 8 or 8.1

         Signature verification feature in 64 bit versions of Microsoft’s Windows 8 and 8.1 sometimes become a mess when you have to install some drivers and the program compatibility assistant just pops up telling you that you cannot install this driver on this computer or it blocks the installation of the driver and required you to check the digital signature on the developer’s end.
Basically, Signature Verification contains an Electronic-Fingerprint that determines whether the driver is developed by the same manufacturer as that of the device’s and also whether the driver has been modified or not (it’s digitally signed or not). The only purpose of Driver Signature Verification is to improve the security of the hardware of the device so that invalid or malfunctioned driver does not cause any harm. The reason we’re here today is already explained above, but needs a little more light, so to make it clear I’ll just share my very own experience.

1. Move your Mouse Pointer to the right side of your PC’s screen in order to get into the configuration bar in Windows 8.
2. Click on “Settings” now.
3. 
4.   In settings, click on “Change PC Settings”.
5. 
6. Once in PC Settings, click on “Update & Recovery”.
7. 
8. In update and recovery click on “Recovery”.
9. 
10. Now in recovery, on the right side you will find Advanced Startup Option.
11. Click on “Restart Now” under the Advanced Startup option.
12.  
13. Your Laptop or PC will restart now, once it boots into the Advanced startup mode, click on Troubleshoot.
14. 
15. In troubleshoot, click on “Advanced Options”.
16. 
17. In Advanced Options, click on “Startup Settings”.
18. 
19. Startup Settings menu will show you the options you can have once you click on “Restart” button.
20. You will now have the choice to pick up the action you want to take, it is most probably Driver Signature verification here. Pressing F7 key will do the job for you. As ssoon as you press the F7 key, your PC or Laptop will reboot having the Driver Signature Verification disabled.
21. 

Thanks All. ^_^

Credit - http://techbeasts.com


Advance Command prompt

Open a command prompt as an admin and type:

bcdedit -set loadoptions DISABLE_INTEGRITY_CHECKS (hit Enter)

bcdedit -set TESTSIGNING ON (hit Enter)

I might have rebooted after that. That put the machine in test mode, like I was going for, and allowed me to install the unverified test driver.

Another Way
  Local Group Policy Editor (gpedit.msc),
go to
User Configuration|Administrative Templates|System|Driver Installation
and set the Code signing for device drivers
policy to Disabled.

Or, if it does not work (because the policy only seems to work on NT5), try restarting the system, pressing F8 when on boot menu and choosing option to start without driver signature verification. Try Shift+F8 as well.